we observed the galactic c ii line emission with bice (the balloon-borne infrared carbon explorer). combining our c ii data with co data, we revealed the galactic arm-interarm contrast in the c ii to co emissivity ratios, which measure star-formation efficiency, under the assumption that the emissivities in our galaxy distribute axis-symmetrically for the galactic center. however, the results depend on this assumption, which is necessary for deriving the emissivities from the edge-on view of our galaxy; this edge- on view prevents us from observing separately the arm and the interarm components. in order to resolve these two components without the assumption of galactic arm structure, we propose to observe a face-on spiral galaxy in c ii 158 micron line with the iso lws. we will reveal the galactic arm-interarm contrast in c ii intensity and in star-formation efficiency in the face-on spiral. for this purpose, we choose ngc300, which is near our galaxy (1.2 mpc) and whose arm structure can be resolved with the lws resolution (approximately 80 arcseconds). combining the present proposal with the previously accepted proposals (obsid kmochizu, propids m31 and m33) and with the bice observations (our galaxy), we can achieve the program revealing far-infrared structure of nearby galaxies with iso and bice. this makes the present proposal appropriate to be submitted for the supplemental call.
Instrument
LWS01 , LWS02
Temporal Coverage
1997-05-18T06:39:45Z/1998-01-20T19:30:16Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the worlds first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
European Space Agency, ISHII et al., 1999, 'SQUARE_BRACKET_OPENC IISQUARE_BRACKET_CLOSE OBSERVATIONS OF SPIRAL STRUCTURES IN NGC 300 A RESEARCH ON ARM-INTERARM CONTRAST IN STAR-FORMATION EFFICIENCY', 1.0, European Space Agency, https://doi.org/10.5270/esa-uwbl774
